I'm finding the 160M dipole thread fasinating.
I have some more antenna test input:
I 've continued to run tests on 160M between my 3 antennas: a three el vert
array, a dipole at 198' broadside NE, and a dipole at 190' broadside SE.
Over the last two months the vertical array was always louder by 6-12 db
into Europe over the 198' high NE dipole. Exceptions are at sunset when they
are close to equal.
However, over the last week or so I find that the vert and dipole are almost
equal at prime night time! I almost thought I had a problem, but then last
night for a short time the condix changed so that the vert took the 8 db
advantage....
So, for whatever reason, it seems this last week with propagation conditions
being down, the dipole is at par.
Now here's the surprising observation: To the SE for S. America - I use
just the single vertical for now with the parasitics out of the circuit. The
dipole at 190' broadside SE is always at least 6-10db louder than the single
vertical! This has gone on for three months now at prime night time.
When on the high dipole, sometimes a SA station will stop a run and ask
"what is your antenna, OM"? ..:-) - never happens with the vert - (The
vertical array now has (qty) 270 radials that are close to 300' long under
it - 81,000' of wire).
After seeing the "power coupling" info, assuming I'm interpreting it
correctly, I may be seeing the difference that a good high dipole will
achieve like the modeling shows, when working to the southeast from CT.
To the SE the ground slopes off about 300' down for the next 1/2 mile, so
the effective antenna height may be well over a 1/2 wave length high to SA.
Bottom line... It may be power coupling, temporary conditions, or something
else - but when working S.America I will be using the high dipole, not the
vertical. Maybe once a reflector is added to the vertical in that direction
it will gain another 4-5 db, but the dipole's present 6-10 db advantage is
gonna be hard to make up.
We'll see what happens as the seasons change and report back.
BTW, thanks for all the info on power coupling and static noise/DSP, guys!
73,
Tom, K1JJ
CT
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